Winter battery use question.

[Ray Cover]

Hey all,

Well first off I finally bought me a camper but.... it didn't turn out to be a molded fg camper. I looked at many and there just wasn't one that would work for my purposes. I ended up buying a 16' Rockwood Mini-light that was set up perfectly for my traveling engraving studio/hotel room.

So I took the camper out for its first run for two weeks of primitive camping in Mark Twain National Forest for deer season. I was able to use it as both a living facility and an engraving studio in the forest. It works perfectly for what I bought and set it up for. The issue I ran into with the cold weather is battery use and maintenance.

The first few days it was very mild temps and my battery lasted about three days before having to recharge with the generator. The last weekend it got down to 7 degrees F. When the weather turned off cold like that I had to recharge the battery about every 12 hrs.

I attribute this to two things. First; is that the furnace cycled on and off more in the MUCH colder temps. The first weekend the furnace cycled once or twice a night to maintain the 65 degrees I set the thermostat at. The last weekend it was cycling about every hour and a half to two hours. Secondly; I believe the cold temps severely affected the chemical electrolytic action of the battery itself.

I know cold weather is hard on batteries in general. Have any of you found ways to fight this when camping in cold weather?

I have thought of heating the battery somehow but since batteries can offgas hydrogen the heat source needs to be carefully thought out. I don't know if they offgas enough H to be an explosion risk. That would take more research but I don't want to recreate the Hindenburg on a miniature scale. There is also the issue of having the battery housed right behind my propane tanks. One thing that I did do was put the leftover "hot hands" hand warmers from each days hunt on top of the battery each night and that did seem to help a little. But that is a very expensive way to go if you are not using those hand warmers for hunting to begin with.

I have thought of switching to AGM or Gell Cell batteries. However, after looking into it I find that they are also affected by the cold when it gets down to the real dirty winter temps. Apparently, they can be damaged or destroyed by severe cold. For general use they would hold a charge longer but they have other issues when recharging and the expense and probably won't solve the issue I want to solve.

I am planning to get a solar panel charger on a stand and a small wind generator that I can fly on a mast attached to the tongue. I do believe this set up will help and cause me to have to use the gas generator a lot less in those situations. But it still doesn't solve the issue of power loss due to severe cold.

In short, do any of you have ways of making your batteries last longer in off grid winter use?

Is there a safe way to keep your battery warm?

I welcome any thoughts on this that you all have.

Ray

[Byron Kinnaman]

Originally Posted by Ray Cover

Hey all,

Well first off I finally bought me a camper but.... it didn't turn out to be a molded fg camper. I looked at many and there just wasn't one that would work for my purposes. I ended up buying a 16' Rockwood Mini-light that was set up perfectly for my traveling engraving studio/hotel room.

So I took the camper out for its first run for two weeks of primitive camping in Mark Twain National Forest for deer season. I was able to use it as both a living facility and an engraving studio in the forest. It works perfectly for what I bought and set it up for. The issue I ran into with the cold weather is battery use and maintenance.

The first few days it was very mild temps and my battery lasted about three days before having to recharge with the generator. The last weekend it got down to 7 degrees F. When the weather turned off cold like that I had to recharge the battery about every 12 hrs.

I attribute this to two things. First; is that the furnace cycled on and off more in the MUCH colder temps. The first weekend the furnace cycled once or twice a night to maintain the 65 degrees I set the thermostat at. The last weekend it was cycling about every hour and a half to two hours. Secondly; I believe the cold temps severely affected the chemical electrolytic action of the battery itself.

I know cold weather is hard on batteries in general. Have any of you found ways to fight this when camping in cold weather?

I have thought of heating the battery somehow but since batteries can offgas hydrogen the heat source needs to be carefully thought out. I don't know if they offgas enough H to be an explosion risk. That would take more research but I don't want to recreate the Hindenburg on a miniature scale. There is also the issue of having the battery housed right behind my propane tanks. One thing that I did do was put the leftover "hot hands" hand warmers from each days hunt on top of the battery each night and that did seem to help a little. But that is a very expensive way to go if you are not using those hand warmers for hunting to begin with.

I have thought of switching to AGM or Gell Cell batteries. However, after looking into it I find that they are also affected by the cold when it gets down to the real dirty winter temps. Apparently, they can be damaged or destroyed by severe cold. For general use they would hold a charge longer but they have other issues when recharging and the expense and probably won't solve the issue I want to solve.

I am planning to get a solar panel charger on a stand and a small wind generator that I can fly on a mast attached to the tongue. I do believe this set up will help and cause me to have to use the gas generator a lot less in those situations. But it still doesn't solve the issue of power loss due to severe cold.

In short, do any of you have ways of making your batteries last longer in off grid winter use?

Is there a safe way to keep your battery warm?

I welcome any thoughts on this that you all have.

Ray

The single biggest single effect on battery usage is to change all the lights to LED. I ran a quick test on m 13', with only one of the standard incandescent light on current draw was about 1.5 amps. Replaced 4 fixtures incandescent bulbs with LED bubls and added two LED fixtures. I have two CCFL tubes also. I turned every light on, all 4 LEDs and the CCFLs current draw about 1.5 amps. I have modified the two fixtures so I can set them to run at 2/5 of normal current, I've found that is enough light for most of the time. (2/5 current is about .08 amps.)

The other thing is consider 55° at night instead of 65°. We use 40° to 50° sleeping bags so 55° works just fine.

When I was in 5° weather I had to use the solar panel everyday, normally I only drag it out every 3 or 4 days. The furnace is the biggest current draw, the more it has to run the quicker you run out of battery. I don't think the cold weather has that much to do with battery performance. You can't equate it to how easy an automobile starts vs difficult to start is cold weather. The biggest reason it's difficult to start is the oil is stiff and the engine is difficult to turn over.

[Ray Cover]

All the lights are already LED. That was the first thing I did when I bought the camper.

Cold does effect the performance of a battery. Temp greatly effects the speed and efficiency of chemical reactions and lead acid batteries work off of such a chemical reaction.

[Byron Kinnaman]

Originally Posted by Ray Cover

All the lights are already LED. That was the first thing I did when I bought the camper.

Cold does effect the performance of a battery. Temp greatly effects the speed and efficiency of chemical reactions and lead acid batteries work off of such a chemical reaction.

I guess I should have put on my engineering hat and said "I doubt that that much cold would make a significant difference". We can go through a whole lot of things that might or might not make a difference, but significance is a different matter.

The battery also generates heat when current is being drawn from it, you gotta factor that in. How much heat? Now you gotta figure out how much heat is created vs current.

In effect I answered your question, that I don't think it's significant enough to worry about. If you were getting into the -40° area you might, but I still doubt it would be enough you could tell the difference.

The exception would be if the battery is mostly depleted in very cold weather (-30° to -40°F) the electrolyte could freeze thus breaking the case.

[Carol H]

Originally Posted by Ray Cover

In short, do any of you have ways of making your batteries last longer in off grid winter use?

Is there a safe way to keep your battery warm?

I welcome any thoughts on this that you all have.

Ray

Ray, I am going to assume this is a new battery that you know its history? ie its less than 5 years old and its never been run down below 40% (11.9). If its a used new to you battery buy yourself a new one, along with a small battery monitor so you can keep it in good shape. It only takes running the battery down a couple of times for its ability to hold a charge to be seriously impacted.

A solar panel would be your best bet - put it out and leave it out. They work fine in the cold.

[steve dunham]

You stated that you only get 12 hours out of your battery at cold temperatures so even if the modifications you listed got you a 50% increase in battery life you still have a problem (12 hours +50%=18 hours . If you do not want to run a generator the only solutions I see are ,camp at a site with electricity or follow Byron's suggestion and add a solar charger. I do not see a way to run your furnace @ 65 Deg F ( 7 Deg F outside ambient) for 3 or 4 days on a single battery without a source of recharge

[Ray Cover]

Originally Posted by steve dunham

You stated that you only get 12 hours out of your battery at cold temperatures so even if the modifications you listed got you a 50% increase in battery life you still have a problem (12 hours +50%=18 hours . If you do not want to run a generator the only solutions I see are ,camp at a site with electricity or follow Byron's suggestion and add a solar charger. I do not see a way to run your furnace @ 65 Deg F ( 7 Deg F outside ambient) for 3 or 4 days on a single battery without a source of recharge

A lot of the places I go do not have electric so I need to come up with some type of power maintenance solution.

I do plan to use a source of recharge. That was never in question. As I pointed out, solar panel and a portable wind generator (like they use on yachts) were a couple things I was considering. I am looking for a way to not have to run that noisy generator every morning and every evening in very cold temps.

Do any of you have a suggestion for a solar kit or brand of panel/contrtoler? I would like a set up where I can run both the panel and the wind generator through the same charge controller. Most of the time around here in winter if the sun isn't shining the wind is blowing so I think incorporating both would be a good idea.

I have also thought of running two or three batteries in parallel to have a larger well to draw from so to speak. Are there any potential problems with doing that?

[Ray Cover]

Originally Posted by Carol H

Ray, I am going to assume this is a new battery that you know its history? ie its less than 5 years old and its never been run down below 40% (11.9). If its a used new to you battery buy yourself a new one, along with a small battery monitor so you can keep it in good shape. It only takes running the battery down a couple of times for its ability to hold a charge to be seriously impacted.

A solar panel would be your best bet - put it out and leave it out. They work fine in the cold.

Good point Carol, I bought the camper used and I am not sure if the battery is a new one or not.

[Carol H]

Originally Posted by Ray Cover

Good point Carol, I bought the camper used and I am not sure if the battery is a new one or not.

Ray as others have suggested even if the battery is in really good condition I would not expect to get 3 days out of it if I kept the furnace on all night long. The furnace is a power hog.

Solarblvd.com has a big sale on today.

[steve dunham]

I just finished sleeping in an unheated pole barn for the first 5 nights of Wisconsin deer hunting (Temps around zero with 20 to 30 MPH NW winds) so I cam empathize with you on running the furnace . My plans with my Casita are to add a second battery plus a 100 watt to 135 watt solar charger . I used to do the electrical for Jacob's Wind wind generators and question whether they are practical in our application . Having a rotating piece of equipment that is accessible to the public and capable of tipping over or loosing a blade presents safety issues . I think solar is much safer ,requires far less maintenance , would be easier to assemble and erect plus has a much lower initial cost

[Dave Fish]

Originally Posted by Ray Cover

I have also thought of running two or three batteries in parallel to have a larger well to draw from so to speak. Are there any potential problems with doing that?

That might be a good option if you have the space. You could even set it up only when you need the extra draw. Many larger RVs have two or three house batteries.

[stevebaz]

You may consider using a propane only Catylitic heater by day while your awake and use the furnace at night while your sleeping. That would drop your battery power consumption by 60 % or so.

[Ray Cover]

Thanks for the input everyone. I talked to a friend of mine who is an electrical engineer and is really into alternative energies. After talking with him, and doing a bit more research, here is what I have decided to do.

I have an area on the tongue behind my propane tank cover for a platform the is 16" wide and 48" long. The platform will be made with an angle iron frame and an expanded steel "floor". On this platform I can fit 3 deep cycle marine batteries and a good size pwm charge controller. Two covers will be made out of FG or kydex thermal-plastic to cover this platform to keep it all out of the weather. One cover will be vented for summer use and the other will be insulated for winter use.

I will add a solar panel set up for daytime use and a small wind generator like they use on sailboats for night time use. I will get a charge controller large enough to handle having both "plugged in" at the same time.

I am also planning to get some of the 1/4" fan fold foam board insulation at the HDWR store and laminating heavy duty white tarp to each side of it and make underpinning skirting out of it that snaps on all the way around the camper.

This system should be redundant enough that I shouldn't have to use the gas generator very often if at all. Within the next few months I am going to be full-timing it in this camper so it will be worth the investment.

Again, Thanks for the input folks.

Ray

[deryk]

Also check the amp hour rating of the batteries. My ParkLiner originally had 2 55ah batteries...which gives you about 55ah of power(shouldn't discharge it more then half way.) The blower on the furnace uses about 2.7ah so under ideal conditions that's about 20 hours of run time. My new batteries are 75ah each so about 75ah of power which gives me about 27 hours of run time before needing to be charged.

I also boondock without power available so a generator comes in handy. Solar would help a lot...I don't think wind power is a good choice. It needs to be high enough up that some idiot doesn't stick their fingers in it and sue you.

At night after the trailer is warmed up I push the thermastat down to its lowest setting and snuggle up under a pile of blankets. Morning comes, I turn the heat up and wait for the caravan to warm up then get out of bed to make coffee. I agree for daytime use a catalytic heater would save you electricity... I just don't reccomend it at night. Some people do, if your feeling daring like that add a co detector.

[Donna D.]

Hi Ray. Sorry you were unable to find an all molded towable, but I'm betting you're going to really like your Rockwood Mini-Lite as it will probably suit your needs.

Did you know there's a Mini-Lite group that hangs out over on the Forest River forums? Since it's targeted to your build type, they'll be able to give you better ideas of the systems and usage of the Mini-Lite than we will. Here's a welcome thread: Forest River Forum - Rockwood Mini-Lite

Best of luck!

[David B.]

Ray, you might also place some insulation in the window openings to help keep the heat inside. Many here use the reflectix bubble insulation for this.
Dave & Paula

[Ray Cover]

Thank you for the lead Donna.

[Roger C H]

Maybe you could find a solution in the boating world.

As a former boater, I know that there are a lot of things made for boats that would really by useful in an RV. They usually are expensive because of being made for a marine environment.

The first two require installation with a flue, etc. The alcohol one is portable and you would have to keep a window cracked. But none of these require electricity!

Wood:

SIG MARINE Cozy Cabin Solid Fuel Heater at West Marine

Propane heater:

SIG MARINE Heater at West Marine

Alcohol heater:

ORIGO Heater at West Marine

[deryk]

If I was going to be staying in my ParkLiner for extended points during the winter I would use this DickinsonMarine.com - Propane Fireplaces

I had one on a boat that I lived on...the fan needs to run for a bit when you first light it to get a good draft...after that you can shut it off or down so the energy use would be low.

[accrete]

we utilized a cabin alcohol heater similar to what was linked above inside both our 22' and 41' sailboats. It worked to take the chill off on the colder mornings/evenings. It did put out a bit of moisture...though having ~9 onboard the morgan 41 was max capacity and we were probably most of the issue with CO2.

I would really luv putting in a safe wood burner in the Parkliner!